ARM: dts: msm: add dt support for etm save-restore for msmtitanium

Add the device tree entries that are used to save-restore the ETM
registers across the CPU power collapse.

Change-Id: Ie4e5e62c1ad2c26c7dee9cbf5b5183a032fdc4d5
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>